Elevator door operator



June 5, 1934. Q NORTON 1,961,938

ELEVATOR DOOR OPERATOR Filed March 7, 1929 2 Sheets-Sheet l INVENTORATTORNEY6 June 5, 1934. c. NORTON ELEVATOR DOOR OPERATOR 2 Sheets-Sheet2 Filed March 7, 1929 ATTORN EYS 1 Patented June 5, 1934 UNITED STATESELEVATOR DOOR OPERATOR Clifford Norton, South Orange, N. J., assignor,

by mesne assignments, to Otis Elevator Company, a corporation of NewJersey Application March 7, 1929, Serial No. 345,139

Claims.

This invention relates to improvements in door operators, the apparatusdisclosed being designed primarily for use with elevator doors.

It is a primary object of the invention to pro- 5 vide power mechanismfor opening an elevator door by a graduated movement operating slowlyduring the initial and final movements of the doors and more rapidlyduring the intermediate portion of the movement and to embody in such amechanism connecting devices between the power means and door subject tothe graduated movements of said power devices permitting the use ofrelatively weak friction devices for adapting the motor or door forindependent operation.

Other objects relate to the provision of power mechanism for operatingthe doors serving to release any object caught in the door by continuingthe operation of the power mechanism.

It is a still further object to provide devices of this character havinggreater safety features than those heretofore employed and which willpermit an occupant of the car to halt the movement of the door or evento move it in an elementary way for example by engagement with the doordirectly after which the door will be again operated to either open orclose the same without further operation of the control mechamsm.

These and other objects will appear more fully from the followingdescription when considered in connection with the drawings in which:

Fig. 1 is an elevational view of the motor operated mechanism andcontrol device and illustrating the connection for the car door andlatch for the landing door.

Fig. 2 is a view similar to Fig. 1 showing the car door moved to openposition.

Fig. 3 is an elevational .view taken at right angles to Fig. 2.

Fig. 4 is a plan view of the apparatus shown in Fig. 2.

Fig. 5 is a detail view of the friction device employed.

Fig. 6 is an enlarged detail view of the landing door lock and switch.

Fig. '7 shows one system of electrical control which may be employed.

The apparatus described in detail herein is primarily designed foroperatorless elevators of the pushbutton type wherein the passengercalls the car to a floor after which the car gate or door will be openedautomatically and the landing door unlatched to permit the passenger toenter the elevator. Thereafter by pushing a suitable control button thecar door is moved to closed position and upon the closing of the landingdoor the elevator automatically moves to. the selected floor and the cardoor and landin doors are again automatically controlled. The car dooroperating devices are complete in themselves and may be used with orwithout the control for the landing door latch.

It is found with this type of elevator that the operating mechanism musthave a high factor of safety providing among other things for theoccasional low intelligence or extreme nervousness of passengers so thatin case the doors do not move automatically to open position in theusual manner or in case the door is moved to closed position before apassenger is fully in or out of the car the door or doors may be movedor halted readily by the passengers grasping the doors directly, thepresent invention also providing for continued operation of the powermeans to release any object caught in the door.

The present invention provides the above desirable features by thefollowing described devices. The elevator car is indicated generally at10, the car being controlled by any usual hoisting control apparatuspreferably of the pushbutton type for moving the elevator vertically tothe different floors of the building.

The door moving mechanism, in the present embodiment of the invention.includes an electric motor 18 mounted upon the car and-connected bymeans of suitable reduction gearing 20 to a slow-speed drive shaft 22formed with a crank arm 24. The motor 18 is arranged to operate inpnedirection only to cause the arm 24 to move through an angle ofsubstantially one hundred and eighty degrees to open the doors and thenthrough the remaining one hundred and eighty degrees to close the same.1

The car gate 26 is connected directly to the eccentric portion of crank24 as by means of the v 95 gate operating lever 28 pivotally mountedupon the car as indicated at 29 and connected through a suitable link orother connection to the door adjacent the outer face of the same. Theupper end of lever 28 is pivotally connected to slide block 32 receivingthe pitman rod 30 which is pivotally attached to the eccentric bearing31 of crank 24 to be moved longitudinally upon rotation of theeccentric. Rod 30 is thus imparted with oscillatory motion. The rod 30is formed with an extended bearing surface on both sides of the device32 to permit complete rotation of the crank 24 while the door 26 is heldeither completely closed or completely open. This is accomplished withthe construction shown without applying unyielding driving force to thelever 28 or disassociating the parts.

The connection 32 between the lever 28 and rod is shown in the presentembodiment as of the friction type capable of permitting free slidingmovement between the rod 30 and lever 28 without undue strain upon anyof the operating connections and preferably without materiallyinfluencing the operation of the motor 18. This connection, as indicatedin detail in Fig. 5, com prises a casing 33 loosely receiving the rod 30and provided with radial bores receiving friction plunger-s 34,preferably formed of bakelite, which as shown are pressed intofrictional engagement with the rod 30 as by means of the springs 35compressed by suitable machine screws. It is found that by forming therod 30 of brass and the plungers 34 of bakelite the friction device ispractically indestructible in normal use of the apparatus. This is thepreferred form of friction connection between the motor 18 and door 26although it will be understood that other types of constantly effectivefriction devices may be employed, the main requirement being to permitoperation of the motor independently of the car gate or movement of thecar gate or door independently of the motor.

The lever 28 is connected to the casing 33 by means or" a pin 36 passedthrough a transverse opening in the casing 33 and held against turningin the housing by a suitable set bolt. The pin 36 is formed with atransverse opening loosely receiving the rod 30, the exposed ends of thepin being received within the openings formed in the upper yoke shapedend of lever 28. The casing 33 and pin 35 may be suitably bored toaccommodate an oil cup as shown in Fig. 5, thus further decreasing thefriction between the rod 30 and friction device 32.

The lever 28 carries projections 3"! and 38 which operate upon theinsulating plungers of the limit switches 39 and 40 to open the controlcircuits for the motor 18 when the door arrives at substantially open orclosed position. In order to open the control circuit for either openingor closing movement at exactly the right point, the abutments 37 and 38are adjustably mounted with respect to the lever 28 as by means of thebolt and slot connections as shown.

The car door may be provided with a handle 27 to permit movement thereofmanually in either direction.

While the control for the door motor 18 may be accomplished in variousways, the wiring arrangement indicated in Fig. 7 is preferred. In thisfigure the door motor 18 may be supplied with electric current acrossthe two supply lines as shown, either through resistance 42 or 43, oneeirective normally during the opening movement of the door and the otherduring the closing movement. These resistances are adjustable so thatthe necessary power may be supplied to the motor for opening and closingmovements.

The control for the motor 18 for opening the door includes a manuallyoperable pushbutton 44 which, when closed, energizes a coil 45 to closethe contacts 46 and 47. The contacts 46 form a holding circuit aroundthe pushbutton 44 for maintaining the coil 45 energized until thecircuit is independently brol-zen by'the opening of the open limitswitch 39. The holding circuit so formed passes from the positive sideof the power line to the stationary contact of switch 44,

through closed contacts 46, to the base of push button 44, through coil45, open limit witch 39 to the negative side of the line. The contacts47 serve to close the circuit to the motor 18 through the contacts 47and resistance 42. The circuits and devices for controlling the motor 18during the closing movement of the door are substantially the same asfor the door opening movement and include a close pushbutton 48 andcontrolling coil 50. The coil 50 controls contacts 470. for closing theholding circuit therefor and contacts 460: for supplying current to themotor 18 by way of resistance 43 when the coil 50 is energized. Theholding circuit during door closing movement passes from the positiveside or the line, through the stationary contact of switch 48, throughcontacts 47a to the base of switch 48, through the door closing coil 50and close limit switch 40 to the negative side of the line. When thedoor is substantially closed the close limit switch 40 opens the circuitto the coil 50 and deenergizes the motor 18.

It is preferred to control the door motor automatically so that wheneverthe car is stopped at a floor the door is automatically opened. Thisarrangement is shown in Fig. '7 and includes a relay the coil of whichis connected across the hoisting motor circuit. The armature of therelay is elevated to the doited line position shown whenever anysubstantial current is supplied to the h isting motor. The armature ofrelay 51 carries a suitable conductor 49 engageable with the upperconducting surface of lever 52 only when the armature drops past thelever on deenergization of the relay. The conductors carried by lever 52and by the armature of relay 51 are included in a short circuit aroundthe open push button 44. The contact lever 52 normally held in positionto be engaged by the armature of relay 51 by any suitable means.

By means of this construction the door opening circuit is closedwhenever the hoisting motor ll. 2

is deener ized and due to the holding circuit formed by contacts 46 theopening circuit is maintained until the car door is open and the openlimit switch interrupts the controlling circuit.

It will be understood that either automatic or manual operation may beemployed or that both may be included in the completed apparatus.

The hoisting motor circuit is preferably rendered inoperative by meansof a circuit controlling switch 54 carried by the car and effective toopen the elevator motor controlling circuit when the car door is movedslightly toward open position. As shown the switch 54 includes contacts56 adapted to be separated by an insulating plunger 58 as the dooropens. Plunger 58 is operated by a lever 59 connected by a suitable linkto the lever 28 to control the plunger directly from said lever. Asindicated in Fig. 1 the plunger 58 permits contact between the members56 only when the car door is substantially closed.

The above described car door mechanism may be employed in connectionwith the various landing doors adjacent which the elevator is stopped tocontrol the locking devices of such landing door. These devices includeat each landing a door latch lever 62 engageable behind a keeper 64carried by the door 65 to lock the door in substantially closedposition. Each landing door preferably has the usual spring or othermechanisin (not shown) tending to move the same to closed position.

As shown the latch member 62 includes an operating arm 66 formed with aroller or other bearing 68 engageable by the cam '70 carried by the car.Cam '70 is mounted upon suitable links andis movable upwardly toinoperative position by means of a chain72 which is passed over thenecessary guide rollers and attached to the upper end of a car doorlever 28. The chain 72is so arranged as todraw up the cam '70 andretract the same as the car door 26 reaches substantially closedposition. The cam 70 is permitted to drop into projected position assoon as the lever 28 has been moved slightly from its door closed position, the projection of cam '70 unlocking the landing door if theelevator is within a predetermined position of the landing, determinedby the length of thecam 70.

According to the present invention an interlock switch is associatedwith the door latch, this switch including conducting members 74 and '76arranged in series in the motor control circuit and positioned to bebridged by a conducting member 7'7 formed as a part of the latch member64, the members 74 and 76 being bridged only when the latch members 62and 64 are in cooperative relation in the locked position of the door.Operation of the elevator hoisting motor is thus prevented unless thelanding doors are all looked in closed position. 7

The apparatus operates as follows: While the car is travelling in theshaft the crank 24 is at the extreme righthand position, as viewed inFig. 1. This maintains the lever 28 and cam 70 in the positions shown inFig. 1. When the car stops at a landing, current is automatically,supplied to the coil of relay 45 so that contacts 46 and 47 are closedand maintained closed by the holding circuit shown whereby current issupplied through the resistance 42 to the motor 18.

Operation of this motor causes the crank 24 to move through an arc ofabout 180 to the position shown in Fig. 2 wherein the car door 26 is in'open position. As the car door begins its movement toward the openposition the interlock' switch 54 is operated to prevent furthermovement of, the elevator car. The initialmovement of the lever 28 andcar door 26 drops the cam 70 thus unlocking the landing door and openingthe interlock switch at the floor at which the car is stopped. When thecar door 26 reaches substantially open position the open limit switch 39is actuated to open the holding circuit through the relay 45 thusdeenergizing the motor 18. Thereafter, through suitable devices such foreX- ample as the pushbutton 48, the door closing circuit may be closedby the relay 50 to form a holding circuit for the coil and to supplycurrent to the motor 18, through the resistance 43, for continuing theinterrupted operation of motor 18 in the same direction as during theopening movement thus closing the car door 26. Just prior to completeclosure of the car door the elevator control switch 54 is permitted toclose and the cam '70 is elevated to its inactive position by lever 28and cable 72. This looks the landing door closed and closes the elevatormotor control circuit. If the landing door should not be in closedposition at this time the downward movement of latch 62 will not permitelevator movement but instead the elevator controlling circuit ismaintained open until the latch 62 engages behind the keeper 64 as thedoor 26 reaches substantially closed position. As the lever 28 reachessubstantially the position shown in Fig. 1 the close limit switch 40 isopened thus deenergizing coil 50 and motor 18.

If during the opening movement any obstruction to the movement of thecar gate 26 occurs the friction device 32 permits the rod 30 to movewith respect to the door lever 28 with the result that the crank 24moves through its normal opening movement of substantially 180 withoutcarrying the gate 26 correspondingly. Since the open limit switch 39 isnot opened unless the car door 26 reaches substantially open positionthe motor 18 and crank 24 continue their movement after reaching theirnormally open door position and the gate 26 is then moved back to closedposition. The motor 18 and crank 24 will then continue to operate andafter moving the door to closed position will reopen it without furtherattention. The person or article previously caught in the door is thusset free but without interfering with the ultimate opening of the doors.

Substantially the same results take place if an obstruction isencountered during the closing movement of the car gate in that themotor 18 and crank 24 continue their movement to the normal positionoccupied thereby at closed door position but, if the door 26 has beenstopped and is not permitted to move to closed position, themotorcontinues to operate thus moving the door back to open position and thento closed position, at which point the close limit switch is actuated tobreak the holding circuit to the coil 50.

If a person is present in a car but through some fault of the mechanismthe door is not moved to open position when the car arrives at thelanding, or when the pushbutton 44 is pressed, the passenger may graspthe handle 27 of the car door 26 to move it to open position. This doorwill remain in any position in which it is placed under theseconditions. Thelanding door may then be moved manually to open positionto permit the person to escape from the car. The opening of either thecar door or landing door prevents movement of the car.

Having now described my invention, I claim:

1. In a door mechanism; a motor; a crank; means for rotating said crankupon rotation of said motor; a door; and means, connecting said crankwith said door, normally effective tomove the latter upon actuation ofthe former by said motor, said means including a longitudinallymovablerod connected to said crank, a door moving member connected to saiddoor, and a constantly effective friction device associated with saiddoor moving member and bearing exteriorly upon said rod so as to benormally movable with said rod but movable longitudinally relatively tosaid rod when the force attempted to be transmitted through saidfriction device is in excess of that which the friction device iscapable of transmitting without slipping.

2. In a door mechanism, a motor, a crank, means for rotating said crankupon rotation of said motor, a door, means connecting said motor anddoor for moving the latter by actuation of the former, said meansincluding a longitudinally movable brass rod, friction devices includingbakelite friction material bearing directly on said rod to cause saidfriction devices to be normally movable with said rod but movablelongitudinally relatively to said rod under abnormal conditions.

3. Operating mechanism for a door, comprising; a member; meansconnecting said member to said door, said means including aconstantlyeffective friction clutch, so that, when there is no slippingat said friction clutch, said member moves between two limitingpositions as said door moves between door-open and door-closedpositions; a motor; an operating shaft driven by said motor; meansconnecting said shaft with said member so that a half revolution of saidshaft in a predetermined direction moves said member from one of saidlimiting positions thereof to the other of said limiting positions;means, effective when said door is in the position normallycorresponding to said first-mentioned limiting position of said member,for actuating said motor so as to rotate said shaft in saidpredetermined direction, thereby normally effecting movement of saiddoor toward its other position; and mechanism responsive to the positionof said door for stopping said motor when said door substantiallyreaches said other of its positions, said means connecting said shaftwith said member being effective, after said shaft has rotated saidone-half of a revolution and driven said member from its first-mentionedlimiting position to its other limiting position, and in the event saidmotor continues to drive said shaft in said predetermined direction dueto the fact that slippage has occurred in said friction clutch with theresult that said motor-stopping mechanism is not operated, to move saidmember back to its first-mentioned limiting position and thereby effeetthe return of said door to its initial position.

4. Operating mechanism for a door, comprising; a motor; a crank; meansfor rotating said crank upon rotation of said motor; a member secured tosaid crank and driven thereby; means connecting said member to said doorfor opening and closing said door upon operation of said motor, saidmeans including a constantly-effective friction grip capable of slippingat any point in the movement of said door when the force attempted to betransmitted through said friction grip is greater than that which thefriction grip is capable of transmitting; means, normally effective whensaid door is in open position, for initiating the operation of saidmotor in the direction to effect closure of said door; and means,effective after the operation of said last-mentioned means, formaintaining said motor in operation in the direction in which it isinitiated,

until said door reaches closed position, so that, in the event said doormeets with an obstruction during closing, slippage may occur at saidfriction grip until said door is urged back toward open position by saidcrank as a result of the continued rotation of said motor, after which,and after said door is returned to open position by said crank, thecontinued operation of said motor recommences the closing movement ofsaid door.

5. Operating mechanism for a door, comprising; a member; meansconnecting said member to said door, said means including a clutchhaving elements between which, in normal operation, there is no relativemovement, so that, in normal operation, said member moves between twolimiting positions as said door moves between door-open and door-closedpositions; a motor; an operating shaft driven by said motor; meansconnecting said shaft with said member so that a half revolution of saidshaft in a predetermined direction moves said member from one to theother of said limiting positions; means, effective when said door is inthe position normally corresponding to said first-mentioned limitingposition of said member, for actuating said motor so as to rotate saidshaft in said predetermined direction, thereby normally effectingmovement of said door toward its other position; and mechanismresponsive to the position of said door for stopping said motor whensaid door substantially reaches said other of its positions, said meansconnecting said shaft with said member being effective, after said shafthas rotated said onehalf of a revolution and driven said member from itsfirst-mentioned limiting position to its other limiting position, and inthe event said motor continues to drive said shaft in said predeterminedclirection, due to the fact that there has occurred an abnormaloperation attended by relative motion of said clutch elements so thatsaid motor-stopping mechanism has not operated, to move said member backto its first-mentioned limiting position and thereby effect the returnof said doorto its initial position.

CLIFFORD NORTQN.

